Means for synchronizing revolving bodies



A June 4, 1 929.

F. SCHWENDNER MEANS FOR SYNCHRONIZING REVOLVING BODIES Filed Jan. 3, 1928 I I I I I I I r ar INVENTOR Afscl'lwendner.

BY Fl wwmvzw;

ATTORNEY Patented June 4, 1929.

ANTHONY F. SCH'WENDNER, OF ESSINGTON, PENNSYLVANIA, ASSIGNOR TO WEST- INGHOUSE ELECTRIC & MANUFACTURING COIvIPANY, A v(7ORTEOJELAGIIlIOli-l' OF PENN- SYLVANIA.

Application filed January 3, 1928.

discs being provided with marks and the other with a series of openings so that, in accordance with the principle of the acetrope, an observer can determine when the bodies are rotating at the same speed by observing the marks through the respective openings.

Such devices, are unsatisfactory for determining the relative speed of bodies which are very nearly at the same speed for the be rotating at identical speeds, whereas there would. actually be a considerable difierence in speed. Occurrences of this kind may cause considerable damage, especially where large powers are transmitted at relatively high speeds.

More particularly, therefore, an object of my invention is to provide a stroboscopic de vice of the type described which shall embody means for afiording more accurate observation of the indicia and which shall be so constructed as to preclude the possibility of giving an erroneous reading.

Apparatus embodying the features of my invention is shown in the accompanying drawing, in which: i

Fig. 1 is an assembly view of apparatus comprising one form of my invention, showing the manner in which parts are assembled v Fig. 2 is an elevation of the apparatus shown in Fig. 1 after the parts have been assembled;

Fig. 3 shows an elevation of the apparatus shown in Figs. 1 and 2, showing the manner in which the indicia may appear under certain conditions of operation;-

Fig. 4 is an elevation of a muff type coupling,'showing the lower portion of the coupling in section;

Fig. 5 is a fragmentary view of an end MEANS FOR SYNCHRONIZING REVOLVING BODIES.

Serial No. 244,262.

portion of the coupling shown in Fig. and,

Figs. 6 and 7 are fragmentary views showing the manner in which the indicia may appear under different conditionsof operation. 7

According to my invention, a curved, or

otherwise irregular mark, is placed on one i of two relatively rotatable bodies, while the other rotatable body is arranged to obscure a considerable portion of this mark. Preferably, the marked body is cylindrical, and the indicia consists of a helical mark which continues entirely around the circumference of the cylindrical body. By observing the axial displacement of the unobscured portion of the indicia, the relative speeds of the two bodies can be readily determined. A maximum axial displacement of the indicia during one minute would indicate that the marked body was changing its speed with respect to the other body at the rate of one revolution faster, or slower, per minute, depending upon the direction of the displacement.

Referring now to the drawings for a better understanding of my invention, I show in Figs. 1, 2 and 8, a simple form of my synchronizing apparatus indicated generally at 10, and comprising a drum member 11, which is adapted to be enclosed by the cylindrical member 12, preferably the drum member and the cylindrical member are connected to shaft sections, such as the sec tions 13 and 14, respectively.

Extending about the Iieriphery of the drum 11 I provide an obliquely-extending mark 16 which is preferably helical in form. I also provide, on the periphery .of the drum 11, circumferentially-spaced and axi: ally-extending indicia, such as the marked lines 17. The cylindrical member 12 is provided with an opening 18 for exposin'g'a portion of the peripheral surface of the drum 11 and, preferably, the opening 18 is so arranged as to be capable of exposing any portion of the helixlfi should such portion of the helix come opposite the opening.

7 In Figs. 4 and 5, I show my invention embodied in a flexible coupling indicated generally at 20 and comprising gear members 21 and 22, which are mounted upon shaft sections 23 and 24, respectively. The gear members are enclosed by a muff member 26, which is provided with internal teeth 27,-

the latter being arranged to normally engage the gear 22 in all positions of the muff member 26 and being extended a suflicient distance longitudinally of the muff member 26- so that, by sliding the muff member 26 toward the gear 21, the teeth 27 will engage the gear 21, aswell as the gear 22, and thus form a coupling between the gear members. 7

A suitable collar 25 may be provided on the gear member 21 for guiding the latter within the muff 26.

The muff member 26 is provided with spaced collars 28, which provide a groove '29 for facilitating the manipulation of the muff member.

In a coupling of this type, large powers are frequently transmitted at relatively high speeds and it is quite important, therefore, that the 'members revolve at substantially the same speed when the muff member is moved to engage the gear 21.

In order to provide for embodying my invention in a coupling of this type, I place a helical mark, indicated at 31, about the peripheral surface of the teeth of the gear member 21, and I provide an opening 32, in

the muff 26, for exposing a portion of the peripheral surface of the gear 21 when the latter is in its disconnected position with respect to the muff member 26, and, preferably, this opening 32 is so arranged as to be capable of exposing any portion of the helix 31 which maycome opposite the opening 32.

In the operation of the apparatus shown in Figs. 1, 2 and 3, it will be obvious that, when the shafts 13 and 14 are rotating at the same speed, the mark 16 will appear clear and distinct, as shown in Fig. 2, and that the visible portion of the mark will not be displaced axially on successive revo-' minute would show a change of two revolutions per minute, and so on.

Under certain conditions of operation, it is possible that the shafts 13 and 14 may be rotating at widely separated speeds, and

yet the mark 16 may appear to an observer to be in identical positions. For example, assume the member 141 to be rotating at 1,800 R. P. M. and the member 13 to be rotating at .900 R. P. M., the mark 16'would then appear clear and well-defined as shown in Fig. 3, and the visible portion of the mark would not appear to be traveling axi ally, but due to the wide difference in speed of the two members, the axiallyextending lines 17 would be blurred and hazy, as indicated in Fig. 3, and thus, an observer would know at once that the shaft 14 was turning twice as fast as the shaft 13.

The operation of the apparatus shown in Figs. 4 and 5 is similar in all respects as that described with reference to Figs. 1, 2 and 3. When the shafts 23 and 24 are rotating at the same speed the mark 31 will appear sharp and well-defined as indicated in Fig. 6, and will not be displaced axially. In this form of the invention, however, it is not necessary to provide longitudinally extending indicia, since'the edges of the gear teeth serve this purpose. From Fig. 6, it will be clear that the edges of the gear teeth are also well-defined. Suppose, however, that the shaft 23 and the gear 21 turn at 1,800 R. P. M. If the shaft 2 1 and the gear 22 are rotating between 1,350 and 1,800 R. P. M., the visible portion of the line 31 will travel to the right. On the other hand, if the gear 22 is rotating from 900 to 1,300 B. P. M. the line 31 will travel to the left. Fig. 7 shows the hazy and blurred appearance which the edges of the gear teeth willassume when the gear 21 is revolving twice as fast asthe gear 22 and the muff 26. Since the direction of travel and the extent of the axial displacement of the line in a given period of time, as in one minute, may be determined by an observer, it is possible to readily determine the relative speeds of the rotating bodies.

The principal objective, in embodying my invention in a coupling of this type, is to provide means for determining when the coupling members are rotating at the same speed, so that they may be coupled without damage. It will readily be seen that I have provided a simple and eflicient means for enabling an operator to determine when this condition exists and furthermore, that there is no possibility of my apparatus giving an erroneous reading, since the axiallyextending lines 17 in Fig. 1, and the edges of the gear teeth in Figs. 4 and 5 provide a constant check on the observations.

While I have shown my invention in tvo forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shallbe placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claims. What I claim is Y 1. Means for determining the relative angular velocity and phase of rotating bodies comprising a rotatable-body, means providing a mark extending obliquely around the periphery of the rotatable body, and another rotatable body encompassing the firstnamed body, said another rotatable body having an opening for exposing a portion of the mark.

2. Means for determining the relative angular velocity and phase of rotating bodies comprising a rotatable drum member having a helix on its periphery, and a rotatable cylinder enclosing the drum and having an opening for exposing a portion of the helix.

3. A device according to claim 2, and means on the periphery of the drum member providing spaced and axially extending indicia.

t. Means for determining the relative angular velocity and phase of rotating bodies comprising a gear having a mark extending obliquely around its peripheral surface, a cylindrical member having an internally-toothed portion for engagement With said gear and another portion for encompassing but not engaging said gear, said another portion having an opening for exposing a portion of said mark.

5. The combination With a disconnectible coupling of the geared mufli' type comprising gear members, an. internally-toothed muif member arranged to enclose the gear members, said muff member being adapted in one position to engage one of said gear members and in another position to engage said one and another of said gear members, of means providing an obliquely-extending mark on the periphery of said another of said gear members and means providing an opening in said muff member for exposing a portion of the periphery of said another gear member when said mufi member is in said one position.

6. A device according to claim 5 in which the obliquely-extending mark is in the form of a helix.

In testimony whereof, I have hereunto subscribed my name this 12th day of December, 1927.

ANTHONY F. SGHVVENDNER. 

